1. Field of Invention
The present invention relates to an electrical connector, and more particularly to an electrical connector with reduced attenuation, near-end cross talk, and return loss so as to achieve impedance matching and comply with Category 5e of EIA/TIA T568A standard.
2. Related Art
Recently, the quality of electrical lines are required to be sufficiently high in order to meet with the high performance standard of data transmission in the network based communication systems. Moreover, the quality of electrical connectors is also required to enhance in order to meet with the even higher transmission speed. Conventionally, a network communication path consists of a transmission medium and a plurality of electrical connectors. Such transmission medium can be a twisted pair, a coaxial cable, an optical fiber, and so on. Nevertheless, such a network communication path experiences a number of drawbacks, particularly at higher frequencies in the network communication systems, thus degrading the signal quality. The drawbacks can be classified as follows:
1) Attenuation. Attenuation is a phenomenon of reducing the strength of an electrical signal, which becomes severe as the transmission distance increases. PA0 2) Near-end cross talk. Near-end cross talk (NEXT) is a phenomenon that occurs when two signal lines carrying signals with about the same frequency in close proximity to each other causes the frequency of one line to interfere with that of the other. PA0 3) Return loss. Return loss is a phenomenon when discontinuous impedance in the transmission system occurs, in turn causes a reflection in the electrical lines, and thus consumes power.
In the case of Unshielded Twisted Pair (UTP) lines, consisting of two insulated copper lines, are twisted in a predetermined manner. Typically, a twisted pair of line consists of a communication link. Alternatively, two pairs of lines consist of a communication link in some cases. These are simple transmission media commonly employed in computer networks. However, cross talk is found in the transmission media due to capacitive coupling existing between the lines. This cross talk is particularly obvious in higher transmission rate (or bit rate). Cross talk also increases impedance as well as significantly attenuates high frequency signals.
Accordingly, Electronic Industries Association (EIA) and Telecommunication Industries Association (TIA) propose a number of standards. These standards are accepted by Institute of Electrical and Electronic Engineers (IEEE). For example, the EIA/TIA T568A standard is included in the 802.3u standard. The EIA/TIA T568A standard is set out to require that the characteristics of all transmission media and electrical connecting means comply with the limits in accordance with the specifications as well as provide a number of standards for each category. For instance, Category 3 is set out to regulate voice signal lines where the bandwidth is 16 Mbps for 24AWG copper line and 100.OMEGA. impedance. Category 4 and Category 3 are the same except that the former has an allowable bandwidth of 20 Mbps. Category 5 and Category 3 are the same except that the former has an allowable bandwidth of 100 Mbps. As to Category 5e standard with respect to electrical lines, it aims at regulating limits for improving the phenomenon of discontinuous impedance in the transmission medium, and reflection and power loss caused therefrom. In brief, Category 5e has stricter limits than Category 5 with respect to return loss.
A perspective view of a prior art for the electrical connector is shown in FIG. 1 comprising a base 10, a conductor seat 12, and a base plate 13. It is claimed by such prior art that the combination of media and connectors comply with the limits in accordance with corresponding specifications. However, for example, even if the combination of them complies with Category 5e respectively, each of them does not. Element by element, such prior art for electrical connectors is not electrical devices in compliance with Category 5e. Thus, signal quality is degraded in transmission when such electrical connectors are used.
Thus, it is desirable to provide an electrical connector with reduced attenuation, near-end cross talk, and return loss in order to overcome the above drawbacks of prior art.